Progressive supranuclear palsy, which is much rarer than Parkinson disease, affects many parts of the brain, particularly the basal ganglia and the brain stem. (The basal ganglia help smooth out muscle movements. The brain stem regulates critical body functions, such as breathing, heart rate, and swallowing, and helps adjust posture.) Brain cells in these areas degenerate, but why they do is usually unknown.

Locating the Basal Ganglia

The basal ganglia are collections of nerve cells located deep within the brain. They include the following:

Caudate nucleus (a C-shaped structure that tapers to a thin tail)

Putamen

Globus pallidus (located within the putamen)

Subthalamic nucleus

Substantia nigra

The basal ganglia help smooth out muscle movements and coordinate changes in posture.

Symptoms

Symptoms of progressive supranuclear palsy usually begin after age 40.

The first symptom may be difficulty looking up without bending the neck or difficulty climbing up and down stairs.

People with the disorder cannot roll their eyes downward, fix their eyes on a stationary object, or follow a moving object. They may have blurred or double vision. The upper eyelids may pull back, producing a look of astonishment.

Muscles become rigid, and movements are slow. Walking is unsteady, with a tendency to fall backward. Speaking and swallowing are difficult.

Other symptoms include insomnia, agitation, irritability, apathy, and rapid changes in emotion.

In the late stages, depression and dementia are common. Compared with Parkinson disease, progressive supranuclear palsy progresses faster, responds less well to treatment, and results in more severe muscle rigidity and disability, usually within 5 years. Usually, death, often due to infection, occurs within 10 years after symptoms begin.

Physical and occupational therapists can provide exercises to help keep joints limber and help people function better. They can also recommend strategies and safety measures to reduce the risk of falls.

Because progressive supranuclear palsy is fatal, people with this disorder should prepare advance directives, indicating what kind of medical care they want at the end of life.

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